1. Field of the Invention
The present invention relates to a compressor to be used as a power source in a manufacturing facility or as a process compressor, and particularly to a compressor with cooling function for cooling compressed air.
2. Description of the Related Art
As described in Japanese Patent No. 3470410 (Patent Literature 1), a two-stage turbo compressor has been known, as an industrial turbo compressor, in which fluid compressed by a first-stage compressor is further compressed by a second-stage compressor and then discharged. In this turbo compressor, an impeller of the first-stage compressor and an impeller of the second-stage compressor are connected to each other with a rotary shaft, and the rotary shaft is rotated by a drive motor through a gear system. Specifically, the above-described rotary shaft is disposed parallel to an output shaft of the drive motor, and a gear of the gear system is meshed with a central portion of the rotary shaft. Further, the impeller of the first-stage compressor is attached to an end portion of the rotary shaft on the drive motor side, and the impeller of the second-stage compressor is attached to the other end of the rotary shaft.
Moreover, an intercooler is provided between the first-stage compressor and the second-stage compressor, and an after-cooler is provided downstream of the second-stage compressor. Further, air compressed by the first-stage compressor is cooled by the intercooler and then recompressed by the second-stage compressor. The air compressed by the second-stage compressor is cooled by the after-cooler to be discharged to the outside.